WaterFurnace / VisionPro IAQ Problem

[babzog]

Hey good folks!

I've got an older WaterFurnace PremierAT (model ATA040A100CLT) and it's (original) thermostat croaked. My contractor temporarily installed a Honeywell FocusPro t-stat but said it wasn't the right one (I need a 3H/2C one). I then went out and picked up a White-Rodgers 1F95-1277 (but what I really wanted was a VisionPro IAQ).

Well, my IAQ came today and I've installed it. Only problem is, the unit has a big red light on inthe upper right corner of the t-stat case and the screen keeps flashing code 40 (compressor should be on but it's not). It's set in Heat Pump mode. I have the L wire hooked up but the docs for the WaterFurnace seem to indicate that L is for faults only (whereas it seems to me the IAQ uses it for monitoring). I can turn on the compressor and aux heat by cranking the temp up so I'm not sure what I might have messed up in the install.

Willing to post whatever needs to be posted to help diagnose and resolve this. I'd love to keep the IAQ!

I should note... when I had the WR t-stat installed, it would briefly flash "call for service" when the unit switched off. Maybe I should just disconnect the L wire? But then, I'd have no fault reporting, correct? Can the IAQ be set to use L for faults only (no monitoring)?

[Jarredsdad]

Without looking it up, I think fault and monitor is the same thing.

On my way to hit the hay.

Go through the set up menu and record settings. #170 is set to ??

That will help us help.

[babzog]

Hi,

Thanks for having a look. If fault and monitor are synonymous, I'm not sure why then, the unit would say the compressor is not on if L is hooked up. Seems strange? Is it possible the IAQ is actively monitoring (ie: attempting to query) the heat pump through L?

This t-stat is, apparently, a "version 2" unit. Indeed, the difference between the online instructions and my printed copy, includes, on mine, the indication of L for monitoring.

My settings:

160 4
165 0
172 2
174 2
176 1
190 0
200 0
220 E 3
230 E 3
240 4
280 1
300 1
310 5
320 0
330 2
340 0
342 E 0
365 E 0
370 1
372 E 0
379 1
383 3
390 0
400 0
500 E 0
510 E 0
520 E 0
530 1
540 2
580 5
600 80
610 60
640 12
650 60
660 0
670 0
680 2
690 2
700 0
701 0
710 0

While I was noting these down, when I got to about 530, the light came on. When I hit Done, it flashed error 89 at me, then disappeared after a few moments.

[Jay11J]

220 E 3
230 E 3
240 4

Set these all to 3, Auto/E is not going to work with your system.

342 E 0
365 E 0
372 E 0
500 E 0
510 E 0
520 E 0

Set these to 0 (same as above on the Auto/E)

While I was noting these down, when I got to about 530, the light came on. When I hit Done, it flashed error 89 at me, then disappeared after a few moments.

This is normal, I've had this happen to me in the past.

Other than that, all is wired up right.

I am not able to find a manual , but do you have the dehumidfication wired up?


Also, with the fault code, is there anything showing on the air handler's board?

[babzog]

Originally Posted by Jay11J

Set these all to 3, Auto/E is not going to work with your system.

Set these to 0 (same as above on the Auto/E)

Okay... all E's set to the suggested values.

Originally Posted by Jay11J

Other than that, all is wired up right.

I am not able to find a manual , but do you have the dehumidfication wired up?

Also, with the fault code, is there anything showing on the air handler's board?

No, I don't have the vanee hooked up yet.. waiting to see if this unit is going to work with the waterfurnace before I cut and reroute the vanee's wires (to the EIM). The vanee is also really simple ('91 vintage) in that it only has a dehumidistat for the main control (and the option of push button switches in bathrooms, which are not installed). The continuous speed is set at the unit itself. Seems that only two wires go from the EIM to the ventilator anyway so I should be good to go when I do hook it up.

The vanee has no capability of showing a fault (it can show a light on a wall-control to indicate high-speed operation though). When the fault lit up on the IAQ, nothing as well showed on the waterfurnace's LED strip. The error code was onscreen even when the t-stat had reached the set temp and should not have had the compressor on.

Edit: I just checked the voltage on L and there is no significant voltage present. I checked the regular terminals (Y, G, W, etc) by connecting my voltmeter's black lead to common and the red to the terminal (and saw around 24VAC). However, I found that by connecting the leads in that manner to L and C, I saw a "negative" voltage. Reversing the leads (R to common and black to L), I saw about 7VDC and about 18VAC to L. Does that make sense? What voltage (if any) does the IAQ expect to be present on L for normal operation?

[Jay11J]

Originally Posted by babzog

The continuous speed is set at the unit itself. Seems that only two wires go from the EIM to the ventilator anyway so I should be good to go when I do hook it up.

Is this fan on 24/7, or does it cycle on and off?

When the fault lit up on the IAQ, nothing as well showed on the waterfurnace's LED strip. The error code was onscreen even when the t-stat had reached the set temp and should not have had the compressor on.

Has the fault shown up since you've made the changes? (E to 0)

I honestly don't know what kind of voltage is expexted on the L.

Go back to the Dhumid, the question was more for the variable speed of your heat upump, not the Vanee system.

I'll wait till you post back about the fan running on this system.

[babzog]

Originally Posted by Jay11J

Is this fan on 24/7, or does it cycle on and off?

Has the fault shown up since you've made the changes? (E to 0)

I honestly don't know what kind of voltage is expexted on the L.

Go back to the Dhumid, the question was more for the variable speed of your heat upump, not the Vanee system.

I'll wait till you post back about the fan running on this system.

The furnace fan is set to come on periodically (in addition to what it is set to when the compressor kicks on) and the vanee runs 24/7 but boosts to highspeed when the wall control calls for it.

Actually, the question was not with the fan, but rather the fault reporting capability of the VisionPro IAQ wrt the model of WaterFurnace that I have. Even after changing E values to hard-coded values, if I hook up L, I still get the error 40 (compressor not running when it should be), even though the thermostat is turning the compressor on and off.

[Jay11J]

Originally Posted by babzog

the vanee runs 24/7 but boosts to highspeed when the wall control calls for it.

Really no need for that fan to run 24/7. Is there a control on it that you can control it to come on every now and then? What is the model # on this?

if I hook up L, I still get the error 40 (compressor not running when it should be), even though the thermostat is turning the compressor on and off.

With the wire off of L, are you get voltage reading on the L wire itself?

[Jarredsdad]

Can't find any Premier units with model starting ATA, all start with P.

In any case, L is used for lockout. If the unit goes out on Hi, Low press, freeze stat, or anyother safety the L output is energized and a light would also illuminate at the stat to warn the homeowner something is amiss.

Unless the IAQ has a fault light (I don't think it does) don't use the L wire.

[Jay11J]

Originally Posted by Jarredsdad

Can't find any Premier units with model starting ATA, all start with P.

I ran into the same thing.

Unless the IAQ has a fault light (I don't think it does) don't use the L wire.

The IAQ does have the red LED light on top left. that flashes along with the error code.

[babzog]

Originally Posted by Jarredsdad

Can't find any Premier units with model starting ATA, all start with P.

In any case, L is used for lockout. If the unit goes out on Hi, Low press, freeze stat, or anyother safety the L output is energized and a light would also illuminate at the stat to warn the homeowner something is amiss.

Unless the IAQ has a fault light (I don't think it does) don't use the L wire.

Originally Posted by Jay11J

The IAQ does have the red LED light on top left. that flashes along with the error code.

The model is definately ATA040A100CLT. It's an older model (sold in '91, manuf in '90, I believe) sold in Canada, if that helps.

There is no significant voltage present on L when no lockout is present. I say "significant", because the needle on my voltmeter moved when I touched the leads but it was only a "bump". Probably some bleed-through from elsewhere, I suspect.

There is also no voltage present between L and C on the EIM.

Do you find it odd then, that there would be voltage present when the L wire is merely connected to the L terminal on the EIM?

I was studying the wiring diagram for the EIM, (heat pump systems page), which seems to indicate a connection from C to L. Do I need to break the L wire and connect it to both L and C?

[celtics17]

FWIW: I have a WaterFurnace Envision dual speed unit. I also have a VisionPro IAQ. I have exactly the same problems you are seeing with L attached, and the red light on the stat. I leave mine unattached. It works perfectly without L attached, I have tried both pulsed and constant L with similar results.


Cheers,
Rob

[Jay11J]

Just undo the L wire, and if the system have problem, you will know and the control board will flash an error code..

[babzog]

Originally Posted by Jay11J

Just undo the L wire, and if the system have problem, you will know and the control board will flash an error code..

It's unplugged and I will live with it if required. I would like to sort out what's going on with it though... 1. to have an understanding of it and 2. to take advantage of the error reporting capability. The old t-stat had that bright red led which instantly alerted of any issues. Without constantly looking at the t-stat or the furnace, I'd have no indication of an error. Though I'm not an electronics man myself, I could have a circuit built up to slip between the t-stat and the waterfurnace if I knew what the t-stat expected from the connected equipment (ie: how would it know to flash error 40 or 89?

[Jay11J]

I am taking a guess here.. I think the L wire on the IAQ is able to commucate with another honeywell product like say a zone control board.

So on your system there may be a small feed back on the L wire , and the IAQ is thinking that the small feed back is that error that would maybe show up on Honeywell's zone board.

[babzog]

Originally Posted by celtics17

FWIW: I have a WaterFurnace Envision dual speed unit. I also have a VisionPro IAQ. I have exactly the same problems you are seeing with L attached, and the red light on the stat. I leave mine unattached. It works perfectly without L attached, I have tried both pulsed and constant L with similar results.

Interesting that the problem occurs even on the newer WaterFurnace units but thank you for the confirmation nonetheless. What do you mean by "pulsed"?

[babzog]

Originally Posted by Jay11J

I am taking a guess here.. I think the L wire on the IAQ is able to commucate with another honeywell product like say a zone control board.

So on your system there may be a small feed back on the L wire , and the IAQ is thinking that the small feed back is that error that would maybe show up on Honeywell's zone board.

Where do you suppose any feedback would originate from - the IAQ or the furnace? Naive guess, but I wonder if a simple diode (to prevent any signal from leaving the IAQ) would solve that, since the furnace should be the unit generating any fault signal?

[Jarredsdad]

Originally Posted by babzog

I saw about 7VDC and about 18VAC to L. Does that make sense? What voltage (if any) does the IAQ expect to be present on L for normal operation?

There's your problem right there. There should be 0 volt on L until the HP locks out.

7 VDC and 18 VAC is probably bleed through form the old unit control board, which is configurable to operate with a DC or AC stat.

In the industry we refer to 24 volts control power. In reality this can vary. 18 and below things tend not to work, 30 and above things tend to cook. I know the IAQ specs say 20 to 30 vac but its really 24 +/-6.

DC should be 0 off, 10 on.

The control board in your heat pump is freaking out your stat.

Get yourself a SPST 24v relay. Connect L (from the stat) to NO and R (from the board) to Common. Connect L (from the control board) and C from the board to the relay coil.

Should the unit lockout and deliver a TRUE 24v signal to the L output this will deliver a TRUE 24v to L at the stat, EIM.

[babzog]

Originally Posted by Jarredsdad

There's your problem right there. There should be 0 volt on L until the HP locks out.

7 VDC and 18 VAC is probably bleed through form the old unit control board, which is configurable to operate with a DC or AC stat.

Interesting you should say that. WaterFurnace told me I have a "DC Board" (the tan board). My HVAC contractor in the meantime, had installed an AC t-stat. I would have thought that the moment AC hit a DC circuit, the thing would have smoked... but apparently not. The original t-stat specs indicate around 22VDC for the outputs. Again... very confused... what is meant by a "DC board" when the IAQ (An AC stat) is controlling things?

Originally Posted by Jarredsdad

The control board in your heat pump is freaking out your stat.

Get yourself a SPST 24v relay. Connect L (from the stat) to NO and R (from the board) to Common. Connect L (from the control board) and C from the board to the relay coil.

Should the unit lockout and deliver a TRUE 24v signal to the L output this will deliver a TRUE 24v to L at the stat, EIM.

Very cool!

I had to read up on what a "SPST relay" was but it seems this may well do the trick! Do you have a part # I can research/order? I did a search for "SPST 24v relay" and came up with a couple of DC based relays (mostly automotive related), but I couldn't locate one that would handle 24VAC across the contacts. As well, the wiring pins seem to be numbered (30, 87, etc) rather than labelled (common, ON, etc). Probably me just not understanding the specs .. like I said, I'm not an electronics guy.

Thanks for the great idea.. hope I can make this work!

[Jarredsdad]

This will work:


HVACR > Controls > Relays > Relay,Fan,24 Vac : Grainger Industrial Supply

[babzog]

Originally Posted by Jarredsdad

This will work:


HVACR > Controls > Relays > Relay,Fan,24 Vac : Grainger Industrial Supply

Hey, thanks for the link. Just wanted to confirm: The relay specs seem to indicate that the coil (what I'd hook up to the furnace side of things) is rated for 24VAC (and the image seems to confirm that... hard to tell, but it looks like it says "AC only" on it). If my circuit board is, in fact, DC based, will this relay work with the DC voltage?

[Jarredsdad]

No, you would need a DC relay.

Everything I've read on Waterfurnace Units indicates selectable AC/DC with switch 2-8.